Stable microbial granular sludge could be cultivated in a single SBR system with the application of intermittent anaerobic and aerobic reaction mode during the reaction phase.
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The matured granules showed the domination of non-filamentous bacteria that were tightly linked and embedded to one another and covered with EPS. The SVI value of the biomass has decreased from 276.6 mL g−1 to 69 mL g−1at the end the 66 days, also indicating the excellent settling properties of the granules.
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The development of the granular sludge is positively correlated with the accumulation of divalent cationic Ca2+ and Mg2+ in the granules suggesting the role played by the cations in the granulation process.
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The results indicate the viability of the single reactor system for treating textile wastewater under intermittent anaerobic and aerobic phase strategy.
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The OUR/SOUR and SMA analyses indicate the presence of anaerobic and aerobic microorganisms activities in the granular sludge which is capable to perform degradation process both in anaerobic and aerobic conditions.